Process of producing phosphorescent yarn



PROCESS OF PRODUCING PHOSPHORESCENT YARN Harold E. Wadely, Irvington, N. Y., assignor to The Firth Carpet Company, vInc., New York, N. Y., a corporation of New York No Drawing. Application January 27, 1955, Serial No. 484,568

1 Claim. (Cl. 117-33.5)

The present invention relates to textile yarn that is luminous and has the property of phosphorescence, and to a process for producing the same.

The term phosphorescent refers to the continuous emission of light from a substance without any apparent rise in temperature produced after exposure to heat, light, or electronic discharges.

The invention is especially directed to a phosphorescent yarn treated in a particular way to meet the requirements of the floor covering and related industries.

The phosphorescent substances to be described herein are to be distinguished from the familiarly known luminiscent material having the property of fluorescence in which the emission of luminescent light ceases with the removal of the exciting energy.

Phosphorescent pigments are synthetic, inorganic chemicals that have the property of glowing in the dark after previous exposure to daylight, ordinary room lighting or certain other forms of radiant energy. This phosphorescent afterglow lasts from 30 minutes to 10 to 12 hours or more, depending on the pigment, after which it can be repeated again and again by renewed exposure of the pigment to light.

Luminous yarns of one kind or another have long been known in the textile industry. Fluorescent yarns have been used for theatrical fabrics, and some phosphorescent materials have also been used for such a purpose. When floor coverings were made with any of the yarns previously used, the abrasion of walking and scufiing prevented the luminous material from remaining effective for an appreciable period before being worn off the yarn.

Accordingly, the primary object of this invention is to provide a wear-resistant, phosphorescent yarn incorporating a permanently phosphorescent material and a substance capable of providing the required wear protection.

In order to serve these purposes it is essential that the phosphorescent yarn be non-toxic and altogether harmless, and non-allergy producing, so that it may be used without limitation in special fabrics for general home use and related purposes.

It is also a specific and important object of this invention to provide a luminous yarn of the character indicated that may be used by the floor covering industry for markings, bindings, and in the production of textures and patterns having special light effects.

A further and more specific object of this invention resides in the provision of a wear-resistant, textile yarn having the property of stable phosphorescence and comprising fibers carrying a mixture of phosphorescent pigments and light-transmitting resin. The process involved in producing these properties is applicable to any animal, vegetable or artificial spun yarn, with a good range of color. The thus treated yarns may be used in the manu facture of textile fabric floor coverings in accordance with any of the known weaving, knitting, tufting or hooking processes employed in the manufacture of floor coverings.

In accordance with the requirements of the patent aired States Patent "ice 2,787,558 Patented Apr. 2, 1957 of phosphorescent substances in association with the yarn is preferably effected during a process similar to the ones used in the dyeing of yarns. In so doing, the yarn is dipped or bathed in a solution which contains the dye and phosphorescent particles, as well as the binder and resinous material which upon dyeing envelops the particles of phosphorescent substance in such a manner as to permanently integrate them with the yarn and provide substantial safeguard from destructive abrasion in use. The phosphorescent pigments employed are combined with such chemical base substances as zinc sulphide, or zinc sulphide combined with cadmium sulphide, or cadmium sulphide combined with strontium sulphide. Any of the mentioned compounds can be used when mixed with water and necessary binder in the manner set forth hereafter.

The phosphorescent pigments specified herein and appearing in the following examples are those produced by the New Jersey Zinc Company under U. S. Patent No. 2,475,437 as standard articles of commerce. They are further identified by that company as Nos. 2301, 2304, 2330, 2478, 2479 and 2480. Light-transmitting natural or synthetic binders are used with the phosphorescent pigments in the yarn bath. Casein is an example of a natural binder that is suitable, and polyethylene, and polyvinyl acetate are examples from a large number of plastic or synthetic resinous materials that have been used successfully.

The general procedure is to incorporate the phosphorescent material pigments in the fibre or the yarn bath, either with or without previous wetting, and then to add a solution of polyvinyl acetate and casein.

The following specific examples are given:

Example 1 Parts by weight ZnS with phosphorescent base 30 Deceresol OT 25% aqueous (ester of sulfo-dicarboxylic acid such as described in U. S. Patent No. 2,028,091) A Casein solution [100 parts casein, 700 parts H2O,

14 /2 parts borax, 2 /2 parts Dowacide 61----.. 10 Polyvinyl acetate emulsion 10 B20... 49 /2 Total 100 ExampleZ Parts by weight ZnS with phosphorescent base 30 Casein solution [100 parts casein, 700 parts H2O,

14 /2 parts borax, 2 /2 parts Dowacide G] 10 Polyvinyl acetate emulsion 5 H20- 55 Total 100 Example3 Parts by weight Casein solution [100 parts casein, 700 parts H2O,

14 /2 parts borax, 2 /2 parts Dowacide G] ZnS with phosphorescent base 25 Total Above formulae may be used either in combination with a dyeing process or merely by themselves as an impregnating process in such cases where no dyed color is desired on the yarn.

The process for impregnating yarn with any given formula, in its preferred form, is as follows (a) Prepare a well stirred emulsion of resin in water;

into the above-mentioned dispersion and'leave some in such state for aperiod of five to ten minutes;

(:1) 'Remove the yarn from the liquid;

(e) Repeat the immersion and extraction of the yarn (or fibers) as often as may be desirable, depending on the end use of theiproduct;

(f) After completion of the herein given operations dry the yarn (or fibers) at an elevated temperature such as 270F. in-anyconventional manner.

It is to be understood that variations can be made in the details ofithe yarn product and process as disclosed herein without departing from the principles of invention and the'scope of the appended claim.

Having thus described my invention, what I claim as novel anddesire-to secure'by Letters Patent of the United States is:

The process of making phosphorescent face yarn for 4 rugs ,or carpetscomprising impregnating spun yarn-stock with a solution consisting essentially of:

Parts by weight ZnS with phosphorescent base -e 30 Casein solution (100 parts casein; 700 parts H20; 14%. parts borax; 2 /2 parts of a sodium salt of pentachloraphenol') 10 Polyvinyl acetate emulsion 5 H2O 55 removing the thus impregnated yarn-stock from said solution; and then drying the spun yarn at an elevated temperature of the orderof 270 F.

References Cited in the file of this patent UNITED STATES PATENTS 2,033,976 Dreyfus Mar. 17, 1936 2,369,184 Silver Feb. 13, 1945 2,621,134 'Welch- Dec. 9, 1952 2,635,969 Goldstein Apr. 21, 1953 

